It is a crime. It show the same level of evolution in society than stoning in some societies which are either archaic or lack an established authority (Bible, parts of the Islamic world). Those people should be punished for what they did. They would probably get some extenuating circumstances. "Lynching is an extrajudicial punishment meted by a mob. It is an enumerated felony in all states of the United States, defined by some codes of law as "Any act of violence inflicted by a mob upon the body of another person which results in the death of the person," with a 'mob' being defined as "the assemblage of two or more persons, without color or authority of law, for the premeditated purpose and with the premeditated intent of committing an act of violence upon the person of another." Lynching in the second degree is defined as "Any act of violence inflicted by a mob upon the body of another person and from which death does not result."" "The Dyer Anti-Lynching Bill as it appeared in 1922 stated: "To assure to persons within the jurisdiction of every State the equal protection of the laws, and to punish the crime of lynching.... Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That the phrase 'mob or riotous assemblage,' when used in this act, shall mean an assemblage composed of three or more persons acting in concert for the purpose of depriving any person of his life without authority of law as a punishment for or to prevent the commission of some actual or supposed public offense." Lynching during the late 19th century in the United States, Great Britain and colonies, coincided with a period of high imperialistic violence and religious-inspired protest which denied people participation in white-dominated society on the basis of race or gender after the Emancipation Act of 1833." "Title 18, U.S.C., Section 241 is the civil rights conspiracy statute which makes it unlawful for two or more persons to conspire to injure, oppress, threaten, or intimidate any person of any state, territory or district in the free exercise or enjoyment of any right or privilege secured to him/her by the Constitution or the laws of the United States, (or because of his/her having exercised the same) and further makes it unlawful for two or more persons to go in disguise on the highway or premises of another person with intent to prevent or hinder his or her free exercise or enjoyment of such rights. Depending upon the circumstances of the crime, and any resulting injury, the offense is punishable by a range of fines and/or imprisonment for any term of years up to life, or the death penalty." Source and further information: http://en.wikipedia.org/wiki/Lynching